So far I haven’t had any issues with my petg parts in the heat. My barn is only air conditioned by fans, so no real cooling for inanimate objects. Just did a 20ish hour cut and nothing flexed or moved other than my dust collection bucket. Hit 100 here yesterday, and was in the high 90’s to low 80’s during the cut. Though the few parts that are still pla haven’t moved either. That would be the feet, and a couple of the leg parts I think. Oh, and the motor mounts are still pla. I haven’t noticed if the’ve warped or not, still run the router around, so I’ve not looked.